Hi,

I posted yesterday, and whilst I didn't figure out an answer the question about the sequencing of the _put call, I did find another way to get what I need. I wanted to get the index of a sink input after creation, but before it plays, so that I can implement sink-input switching and other stream manipulation (volume changes, etc.) in response to audio policy changes, on an embedded system.

I can't explain why _put is called after the stream completes playback, but I did discover a different way to be notified of sink- input creation with the completely filled sink input, using pa_subscription. Recall that neither sink-input new hook or the sink- input fixate hook will call back with a complete sink-input (the index of the sink-input has not been set with either) and that I was not seeing the sink-input put hook being called until after a stream had completed playback. So the method I came across (modified from one of the existing module sources) is as follows.

Install a subscription routine using in the module init routine:

u->subscription = pa_subscription_new(m->core, PA_SUBSCRIPTION_MASK_SINK_INPUT, subscribe_callback, u);

This allows us to get notifications on sink-input creations. When this routine is called back, it will be passed the index of the created sink input which makes getting at the actual sink-input to inspect it's fields really easy.

Here is a subscribe callback to do this:


static void subscribe_callback(pa_core *c, pa_subscription_event_type_t t, uint32_t idx, void *userdata) {
    struct userdata *u =  userdata;
    pa_sink_input *si = NULL;

    pa_assert(c);
    pa_assert(u);

    pa_log("> pa__init");

    /* we are only interested in sink-input creation events */
if (t != PA_SUBSCRIPTION_EVENT_SINK_INPUT| PA_SUBSCRIPTION_EVENT_NEW) {
        pa_log("< pa__init - not a new sink input");
        return;
    } else {
        if (!(si = pa_idxset_get_by_index(c->sink_inputs, idx))) {
            pa_log("< pa__init - can't get index");
            return;
        }
    }

    pa_log("new event received on sink-input with index %d",si->index);

}

Regards

Nick

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